Does it take more electrical energy to transmit HF and lower frequencies than it takes to transmit VHF and above? Are there any wavelengths beyond radio waves and gamma rays? Is it true that the lower the frequency, the lower the amount of data that's being sent? I read on this wiki that military submarines can only send around 300 bit/s – or about 35 eight-bit ASCII characters per second when sending in ELF, and a few characters per minute when sent in ELF. Is there a chart or an article somewhere showing if there's any relation? If I have an antenna that's ~1cm, will it still be able to pick up and send HF and lower signals? Isotropic antennas can't really be achieved, but what types of antennas are most like isotropic anyway? Thanks a lot for reading. It's ok if you can only answer a few, I just need some help with this.